Question

我正在尝试从数据库中检索数据到我的Laravel CRUD中，但是它在我的视图中显示未定义的变量。

这是view frame.blade.php

@foreach($mahasiswa as $mhs)
   <tr>
       <td>{{$mhs->id}}</td>
       <td>{{$mhs->nim}}</td>
       <td>{{$mhs->nama}}</td>
       <td>{{$mhs->alamat}}</td>
       <td>{{$mhs->fakultas}}</td>
       <td><a onclick="event.preventDefault();editmhsForm({{$mhs->id}});" href="#" class="edit open-modal" data-toggle="modal" value="{{$mhs->id}}"><i class="material-icons" data-toggle="tooltip" title="Edit">&#xE254;</i></a>
           <a onclick="event.preventDefault();deletemhsForm({{$mhs->id}});" href="#" class="delete" data-toggle="modal"><i class="material-icons" data-toggle="tooltip" title="Delete">&#xE872;</i></a>
       </td>
       </tr>
@endforeach

这是控制器

use App\Dashboard;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Validator;

class DashboardController extends Controller
{

public function index(Request $request)
{
    $mhs = Dashboard::orderBy('id', 'desc')->paginate(5);

    return view('frame')->with('frame', $mhs);
}

这是路线

Route::group(['prefix' => 'mahasiswa'], function () {
    Route::get('/dashboard/{id}', [
        'uses' => 'DashboardController@show',
        'as'   => 'mahasiswa.show',
    ]);

    Route::post('/dashboard/', [
        'uses' => 'DashboardController@store',
        'as'   => 'mahasiswa.store',
    ]);

    Route::put('/dashboard/{id}', [
        'uses' => 'DashboardController@update',
        'as'   => 'mahasiswa.update',
    ]);

    Route::delete('/dashboard/{id}', [
        'uses' => 'DashboardController@destroy',
        'as'   => 'mahasiswa.destroy',
    ]);
});

我的视图上不断出现“未定义变量：mahasiswa”

有人知道原因吗？

Answer 1

您正在传递名为frame的数据，并尝试在$mahasiswa上进行迭代，因此可以将刀片更改为：

@foreach($frame as $mhs)
   <tr>
       <td>{{$mhs->id}}</td>
       <td>{{$mhs->nim}}</td>
       <td>{{$mhs->nama}}</td>
       <td>{{$mhs->alamat}}</td>
       <td>{{$mhs->fakultas}}</td>
       <td><a onclick="event.preventDefault();editmhsForm({{$mhs->id}});" href="#" class="edit open-modal" data-toggle="modal" value="{{$mhs->id}}"><i class="material-icons" data-toggle="tooltip" title="Edit">&#xE254;</i></a>
           <a onclick="event.preventDefault();deletemhsForm({{$mhs->id}});" href="#" class="delete" data-toggle="modal"><i class="material-icons" data-toggle="tooltip" title="Delete">&#xE872;</i></a>
       </td>
       </tr>
@endforeach

或在您的控制器中：

public function index(Request $request)
{
    $mhs = Dashboard::orderBy('id', 'desc')->paginate(5);

    return view('frame')->with('mahasiswa', $mhs);
}

Answer 2

尝试这种方式：

首先在控制器中将您的数据库查询结果分配给 $ mahasiswa ：

use App\Dashboard;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Validator;

class DashboardController extends Controller
{

public function index(Request $request)
{
    $mahasiswa = Dashboard::orderBy('id', 'desc')->paginate(5);

    return view('frame', compact('mahasiswa'));
}

然后在视图中：

@foreach($mahasiswa as $mhs)
   <tr>
       <td>{{$mhs->id}}</td>
       <td>{{$mhs->nim}}</td>
       <td>{{$mhs->nama}}</td>
       <td>{{$mhs->alamat}}</td>
       <td>{{$mhs->fakultas}}</td>
       <td><a onclick="event.preventDefault();editmhsForm({{$mhs->id}});" href="#" class="edit open-modal" data-toggle="modal" value="{{$mhs->id}}"><i class="material-icons" data-toggle="tooltip" title="Edit">&#xE254;</i></a>
           <a onclick="event.preventDefault();deletemhsForm({{$mhs->id}});" href="#" class="delete" data-toggle="modal"><i class="material-icons" data-toggle="tooltip" title="Delete">&#xE872;</i></a>
       </td>
   </tr>
@endforeach

它将消除该错误。

我使用了返回视图（“框架”，紧凑型（“ mahasiswa”））； ，即紧凑，而不是带有。我认为对于初学者来说，它更干净，也更容易混淆。

Answer 3

它仍然可以这样工作：

use App\Dashboard;
use Illuminate\Http\Request;
use Illuminate\Support\Facades\Validator;

class DashboardController extends Controller
{

public function index(Request $request)
{
    $data['mahasiswa'] = Dashboard::orderBy('id', 'desc')->paginate(5);

    return view('frame',$data);
}

视图

@foreach($mahasiswa as $mhs)
   <tr>
       <td>{{$mhs->id}}</td>
       <td>{{$mhs->nim}}</td>
       <td>{{$mhs->nama}}</td>
       <td>{{$mhs->alamat}}</td>
       <td>{{$mhs->fakultas}}</td>
       <td><a onclick="event.preventDefault();editmhsForm({{$mhs->id}});" href="#" class="edit open-modal" data-toggle="modal" value="{{$mhs->id}}"><i class="material-icons" data-toggle="tooltip" title="Edit">&#xE254;</i></a>
           <a onclick="event.preventDefault();deletemhsForm({{$mhs->id}});" href="#" class="delete" data-toggle="modal"><i class="material-icons" data-toggle="tooltip" title="Delete">&#xE872;</i></a>
       </td>
       </tr>
@endforeach

未定义的变量：Laravel foreach中的错误

3 个答案: